Electric-arc lamp



(No Model.) v

E. THOMSON.

BLEGTRIG ARG LAMP.

Paentedv Mar. 3,1891.

UNITED STATES PATENT OFFICE.

ELIIIU THOMSON, OF NEV BRITAIN, CONNECTICUT, ASSIGNOR TO THE THOMSON-HOUSTON ELECTRIC COMPANY, OF CONNECTICUT.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 447,383, dated March 3, 1891.

Application filed February 16, 1884. Serial No. 121,028. (No model.)

To @ZZ whom it may concern.-

Be it known that I, ELTHU TnoMsoN, a citizen of the United States, and a resident of New Britain, in the county of llarttord and State of Connecticut, have invented certain new and useful Improvements in Electric-Aro Lamps7 of which the following is a specification.

My invention relates to the general construction of electric-arc lamps; and it consists in certain combinations and details of construction, which will be hereinafter described, and pointed out in the claims, and which are designed, among other things, to render feasible the employment of carbons of small diameter, as also to reduce the length of the lamp and render the lamp more convenient of use.

In the operation of electric lamps itis found that with the ordinary constructions there is considerable diiiiculty in keeping the carbons, especially if of small diameter, in strict alignment during burning. Lamps constructed for the employment of carbons as small as tliree-sixteenths to one-fourth of an inch in diameter have often failed from this cause. In my lamp this diiticulty is avoided by a novel combination with the carbon-car rier of a central bushing and guides, the latter connected with the carrier near the carbon-holder and arranged to bear on side rods or guides, preferably below the level of said holder. Inmy lamp, moreover, the construction is such that the globe may be lowered to permit renewal oi the carbons, while at the same time the arrangement is such that no addition to the length of the lamp is required to secure this result.

Figure l is an elevation of a lamp constructed according to my invention. Fig. 2 is a detail side view of the clamp or clutch employed with the carbon or carbon-carrier. Fig. 3 is a longitudinal cross-section of one side of the guide and the guiderod upon which it bears. Fig. el is a vertical section of the lower-carbon clamp or holder. Fig. 5 is a detail perspective view of the pivoted ringclamp and rod by which the globe is suspended.

Any magnet system may be employed in the lamp to effect the separation of the carbons and the release or feed oi the Janie as they waste away.

D and S indicate coarse and Fine wire magnets of any suitable or ordinary shape, one to be placed in main or principal and the other in a derived circuit around the carbons, as usual in the art, while D2 indicates an armature co'ntrolled by said magnets and serving to impart movement to the clamp, clutch, or other feed-controlling device. These parts are merely typical of such devices in lamps, and need not be described further.

It is the upper carbon rod or carrier, which is guided in a hole in the bottom of the case Il. It is furnished with a cross-head or support Y, which sustains two pieces K, forked or perforated, so as to be guided upon the side bars or parallel guide-rod G G, depending from the lamp. The position of the points of contact of the pieces K K with respect to the carbon holder or clamp E is preferably, as shown, some distance below the latter. This device, acting in conjunction with the hole or guide in ll, serves as an eX cellent steadying and guiding arrangement for preventing lateral displacement of the holder E and consequent sliding by one another oi the small carbons used. The guidepieces K K are insulated from the cross-head or support Y in case the guide-bars G G are also yin electrical connection with and serve as the means of sustaining the lower-carbon holder F, as in the present and preferred construction ot' electric lamps. The guide-bars G G. are hung from an insulated plate P under the lamp-case itself.

To avoid unnecessary length ot' the rod R, the actuating-clutch above the hole or bushing H. This clutch may be any construction adapted to be operated in the position shown. A form suit able for the purpose consists of a body c, Fig. 2, with a hinged cam or j aw .I having an elongated arm extending in a vertical direction, as shown, and provided with a spring s, acting to close said jaw .l upon the rod R. The body c is supported by a link hung from a horizontal arm D4, extending from the fulcrum-point ofA the armature-lever D2. The jaw J is released on thelowering of the clutch O is placed immediately IOO by a bent or elbow lever b, which, being piv The globe is supported in a ring O belowV the lower-carbon holder F, said ring being preferably kept from coming into electrical connection with the holder or its support by means of apiece or pieces of insulating material I2, secured to the ring Oor to the holder F or its support. The ring or support O is itself supported by side rodsl M M, which extend upward around the outside of the globe, and may be moved up and down in suitable guides.

Guides D5 D5 are supported by or from the lamp-case,and preferablyinsulated th erefrom. N N indicate tilting clamps or clutches which are pivoted at one side on stationary supports and surround the rods M M, so as to normally grasp said rods and hold them and the globeholder up while the lamp is in use. When the globe is to be lowered for renewal of carbons or the like, the tilting catches N N are simply lifted to a horizontal position, when the globe and side rods may be let down until the stops T T upon the upper ends of the rods M come into engagement with the catches N N.

Fig. 5 shows the catch N clamping its bar or rod M. l 'A The lower-carbon holder F is mounted, as shown in Fig. 4, so as to permit a slight balland-socket or universal swinging movement to be given to it, so as to bring the end of the lower carbon opposite the end of the upper carbon. G4 is the lower cross bar or plate carried by the rods G G and supporting the lower-carbon holders F.

The holder F is itself of any suitable or proper construction for clampin g or grasping the lower carbon. The plate G4 is centrally' perforated for the admission of the body of the holder F, extended downward for the reception of a nut V screwing thereon. The surfaces of Gf, of F, and of V fit one another upon curved lines, the curves of which are concentric, centering preferably a little above the holder F. The nut serves to clamp the parts in any desired position. When it is loosened, the lower carbon may be pointed in any direction so as to edect a compensation for slight crookedness of carbons.

What I claim as my invention is- 1. The combination, substantially as described, of the upper-carbon rod or carrier guided in a bushing at the bottom of the lampframe, a cross-bar Y, carrying guide-pieces supported by said bar below the carbon-clamp and guided upon the side rods that support the lower carbon, a liftingand feed clamp supported immediately above the bushing at the lower part of the lamp-frame, a lever D4, sustained by said clamp and carrying the armatures for the lamp-magnets, the vertical arm or extension from the feed-clamp, a releasing elbow-lever carried by the lever D4 and arranged to engage said vertical extension, and a stop for the horizontal arm of said lever, as and for the purpose described.

2. The combination, substantially as described, in an electric-arc lamp, of rods G G, carrying the lower carbon, the globe surrounding said rods, exterior rods M, supporting the globe-holder, and the tilting clamps or clutches N, supported from the side of the lamp -casing, as and for the purpose described.

. 3. The combination, in an electric lamp, of the globe-holder, the vertically-sliding rods M, supporting the same, and having stops T at their upper ends, guides D5 D5, secured to the lamp-casing, and clamps or clutches N N, supported from the lamp frame or case above said guides, as and for the purpose described.

Signed at Boston, in the county of Suffolk and State of Massachusetts, this 3d day of November, A. D. 1883.

. ELlHU THOMSON.

llfitnesses:

J osEPH J. SKINNER, H. B. ROQUIS. 

